U.S. patent application number 10/641659 was filed with the patent office on 2004-03-25 for open loop minesweeping system.
This patent application is currently assigned to Edo Corporation. Invention is credited to Cangelosi, Joseph S..
Application Number | 20040055450 10/641659 |
Document ID | / |
Family ID | 25320866 |
Filed Date | 2004-03-25 |
United States Patent
Application |
20040055450 |
Kind Code |
A1 |
Cangelosi, Joseph S. |
March 25, 2004 |
Open loop minesweeping system
Abstract
An open loop magnetic field minesweeping system, with a small
and light weight body to be towed through seawater by a towing
cable from a helicopter or other vehicle, a single sweep cable
extending rearwardly a substantial distance from the body with a
first electrode in cable, sleeve or sock form attached to the end
of the sweep cable, and a second electrode positioned forwardly of
the body to be towed and extending along and connected to the
towing cable. A rectifier and transformer on the body convert AC
power fed to the towed body from the towing vehicle, to DC power
applied across the first and second electrodes. A plurality of
fairings attached to the towing cable each have an electrically
conductive portion electrically isolated from the towing cable. The
electrically conductive portions are electrically connected
together to form the second electrode. Each fairing has a plastic
nose piece attached to the towing cable and an electrically
conductive metal tail piece.
Inventors: |
Cangelosi, Joseph S.;
(Levittown, NY) |
Correspondence
Address: |
Daniel H. Steidl, Esq.
Kilgannon & Steidl
85 Pondfield Road
Bronxville
NY
10708
US
|
Assignee: |
Edo Corporation
|
Family ID: |
25320866 |
Appl. No.: |
10/641659 |
Filed: |
August 15, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10641659 |
Aug 15, 2003 |
|
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09855290 |
May 15, 2001 |
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6634273 |
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Current U.S.
Class: |
89/1.13 |
Current CPC
Class: |
B63G 7/06 20130101; B63B
21/663 20130101 |
Class at
Publication: |
089/001.13 |
International
Class: |
B64D 001/04; F41F
005/00 |
Claims
What is claimed is:
1. A plurality of fairings for use in an open loop magnetic field
minesweeping system having a towing cable and a towed body, each
fairing having a non-conductive portion for attaching to the towing
cable and an electrically conductive portion electrically isolated
by the non-conductive portion from the towing cable, said
electrically conductive portions being electrically connected
together to form an electrode to be powered from the towed body.
Description
[0001] This application is a divisional application of U.S. patent
application Ser. No. 09/855,290 filed on May 15, 2001 naming Joseph
S. Cangelosi as inventor.
FIELD OF THE INVENTION
[0002] The present invention relates to minesweeping equipment, and
more particularly to equipment that will clear a body of water of
mines that can be set off by influence signatures.
BACKGROUND OF THE INVENTION
[0003] A minesweeping system that creates influence signatures
generally must provide a large enough influence field to be
effective while still minimizing the size and weight of the
equipment to make the system practical from the standpoint of the
platform which controls and/or tows the system. This platform may
be a ship, a helicopter, a remote controlled vehicle operating
above or below the water surface, or a slow moving aircraft.
Minesweeping systems generally have therefore involved a trade-off
of performance vis-a-vis size and weight.
[0004] Prior art systems to date have included sweep systems using
open loop magnetic technology, wherein electrical current is
distributed between two or more towed electrodes and the
intervening seawater between the multiple electrodes is used as the
electrical return. One such system, the Mk-105, utilizes a vehicle
towed by a helicopter with a gas turbine power plant on the
hydrofoil to generate electricity for the open loop electrodes. The
Mk-105 system is powerful, but also quite large and heavy, thus
requiring the hydrofoil vehicle. In general, however, the most
efficient means to achieve a large magnetic field is to use the
open loop means of generating the field. Thus, a ship or
helicopter-hydrofoil system has generally been required for the
towing. Further, such open loop systems require sufficient physical
handling equipment to handle the two or more electrodes, including
the appropriate deployment and retrieval of the multiple electrodes
as well as maintaining the multiple electrodes separated from one
another for proper functioning and to avoid tangle.
[0005] An alternative prior art sweep system, for example the SWIMS
system, generates the magnetic influence field utilizing
conventional dipole technology with large magnetic cores. Because
of the size and weight associated with this technology, however,
the magnetic field is limited by the size and weight of a practical
towed body in which the system is housed.
[0006] Still further prior art minesweeping systems have involved
various coils or permanent magnet solutions which also have size
and weight problems that result in limited field strength.
[0007] My pending U.S. patent application Ser. No. 09/545,820 filed
Apr. 7, 2000, discloses an open loop minesweeping system, but one
which is smaller than the above-referenced prior art, lightweight,
and having simplified electrode handling. A body is towed in the
water by a tow cable, the body towing only one (the first)
electrode behind it while still using the open loop means of
generating the magnetic field. This is accomplished by having the
towed body itself function as the other (second) electrode, either
by making the skin of the towed body the electrode or by having
removable panels on the skin of the towed body. AC input power of
low amperage and high voltage is passed from the primary towing
platform to the towed body, the AC power then being transformed and
rectified at the towed body.
SUMMARY OF THE INVENTION
[0008] The present minesweeping invention also is intended to
utilize the open loop means of generating the magnetic field to
obtain a powerful field, while overcoming the deficiencies of the
prior art to provide a smaller system, a lightweight system, and a
system that simplifies electrode handling. The present invention is
sufficiently small and stable that it can be utilized with and
towed by smaller helicopters, smaller water vehicles or remotely
operated vehicles. The invention is adapted to a wide variety of
littoral or deep water operations, for example to clear mined ports
or offshore areas or off a beachhead or deep water areas such as
choke points.
[0009] The present invention includes a body to be towed in the
water by a tow cable, the body containing hydrodynamic control
surfaces and designed to provide a high-speed and stable tow. The
body provides the means to generate the magnetic influence
signatures, and the body may also include transducers to generate
acoustic influence signatures. A significant aspect of the present
invention, as in my above-referenced pending patent application, is
that the towed body also does not tow multiple electrodes behind it
to generate magnetic signatures, but rather only tows one (the
first) electrode behind it while still using an open loop means of
generating the magnetic field. This is accomplished in the present
invention by having the other (second) electrode positioned along
the tow cable itself ahead of the towed body. In particular, a
plurality of spaced fairings may be attached to the tow cable. Each
fairing has a first conductive portion electrically isolated from
the conventional electromechanical tow cable, and a second
non-conductive portion mechanically attached to the tow cable. The
conductive portions of the fairings are electrically connected
together to form the second electrode which is electrically fed
from the towed body. Since the towed body only tows one cable which
contains the first electrode extending behind the towed body, the
physical handling equipment for the single cable is thus
considerably simplified as contrasted with what is needed for open
loop systems handling and towing multiple cables, each with
electrodes. As an alternative to the fairing approach, the other
(second) electrode may be an electrode cable positioned along and
tied to the tow cable.
[0010] Open loop power and control systems generally provide an
input AC power which is then rectified to DC power and controlled
to either continuous level or to relatively low frequency (pulsed)
waveforms. This rectification and conditioning generally are done
on the primary towing platform, i.e., the helicopter or ship, which
requires weight and space, and requires large diameter cables to
handle and pass the large DC currents associated with open loop
sweeps. Particularly when the primary towing vehicle is a
helicopter, the cable with DC power from the helicopter to the
towed body is in air and thus presents difficulties in cooling
absent such a large diameter cable. Accordingly, in a further
aspect of the present invention, as in my above-referenced pending
patent application, AC input power of low amperage and high voltage
is passed from the primary towing platform to the towed body,
enabling the use of a lower weight cable of small diameter that can
be handled by a small helicopter. The AC power is then transformed
and rectified at the towed body.
[0011] Although the transformer and rectifier components would
normally generate excessive and damaging heat at the towed body,
the heat is dissipated in the present invention, as in my
above-referenced pending patent application, by exposing the
transformer and rectifier components at the towed body directly to
the sea water. These components are not retained within a
watertight enclosure with cooling mechanisms, but are encapsulated
within a thin waterproof coating directly exposed to the sea water,
the coating protecting the components from the conductive sea water
but otherwise cooling the components by passing heat through the
thin coating directly to the sea water. Maximum cooling is
obtained, and the components can be of significantly reduced size
and weight from that which would be required by alternative forms
of cooling at the towed body.
[0012] The body to be towed also may contain a winch to deploy and
return the first electrode. The first electrode also may take
alternative forms, such as a cable, a rigid sleeve, or a flexible
sock as disclosed in my above-referenced pending patent
application.
[0013] Other features and advantages of the present invention will
be apparent from the following description, drawings and
claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a schematic view of the present invention as it
would be towed through the sea water;
[0015] FIG. 2 illustrates in detail the towed body used in the
present invention;
[0016] FIG. 3 is a side elevational view illustrating in detail
certain of the fairings including the second electrode elements of
the present invention as positioned along the tow cable;
[0017] FIG. 4 illustrates in perspective one of the fairings of the
present invention; and
[0018] FIG. 5 illustrates the power conversion elements used in the
present invention.
DETAILED DESCRIPTION OF EMBODIMENTS
[0019] Referring to FIGS. 1 and 2, towed body 10 is illustrated
which is generally shaped in a torpedo-like, streamlined fashion
for smooth, fast and stable passage through the seawater 11. Body
10 when towed may be submerged, and includes rear hydrodynamic fins
12 and possibly hydrodynamic wings 13 to control the orientation,
depth and direction of the towed body. As illustrated,
electromechanical tow cable 14 is connected at one end to the towed
body 10 at connector mechanism 15, and the other end of tow cable
14 may be connected to a winch mechanism on the towing platform
(for example on a towing helicopter, not shown). The towing
platform also will have means to cradle and carry the towed body 10
when not in minesweeping use from one location to another. The
towing platform additionally will have power means to provide AC
power of low amperage and high voltage down tow cable 14 to the
towed body 10. As previously noted, the providing of AC power of
low amperage to the towed body allows the power cable along tow
cable 14 to be of small diameter and light weight as compared to
cables providing high DC current from the towing platform to the
towed body.
[0020] Extending rearwardly from towed body 10 when it is in
minesweeping operation is an insulated and waterproof, sweep
separation cable 16 and the aft (first) anode electrode 17 in cable
form. Cable 16 and electrode 17 may be non-buoyant to minimize size
and drag, and are of standard known design. The open loop magnetic
method of minesweeping requires a second electrode, but in the
present invention, there is no second electrode towed behind towed
body 10. Rather, a cathode electrode 18 is shown schematically in
FIG. 1 extending along the electromechanical tow cable 14 in front
of towed body 10. It should be understood that the anode and
cathode functions may be reversed between the respective
electrodes. Electrode 18 is separated from the front of towed body
10 by at least several feet. It is know to utilize a plurality of
streamlined fairings along a tow cable to reduce drag and
strumming, and for stabilizing the tow of body 10. In the present
invention, referring to FIG. 3, a plurality of fairings 30 are
mechanically attached to electromechanical tow cable 14, but at
least a portion of each fairing is electrically isolated from cable
14. Each fairing 30 for example has a plastic nose piece 31 which
surrounds tow cable 14, and a tail piece 32 which comprises
electrically conductive metal which is electrically isolated from
tow cable 14 by the plastic nose piece 31. The metal tail pieces 32
are electrically connected together by flexible electrical
conductors 33 so that the tail pieces 32 of all the fairings 30
form the second electrode 18 of the present invention. Four of such
fairings are shown in blown-up detail in FIG. 3, and an individual
fairing is shown in perspective in FIG. 4. Insulated and waterproof
separation cable 34 extends from the fairing nearest towed body 10
back to the towed body and is connected to the DC power source
situated on body 10 as further described below. As shown in FIG. 4,
each fairing 30 has a hole 41 for tow cable 14 to pass through
plastic nose piece 31. Each fairing 30 further has a hole 42 for
electrical conductors 33 which are connected to each tail piece 32
in any suitable manner.
[0021] First electrode 18, merely as an example, may be from fifty
or less feet up to two hundred or more feet in length, and there
may be for example three fairings p r foot of tow cable 14, for a
total of several hundred fairings. Since the fairings 30 are
capable of moving to a degree along tow cable 14, permanent ring
members may be swaged to cable 14 at given distances (i.e., thirty
feet) to prevent the fairings 30 from excessively bunching up along
cable 14. Accordingly, the several hundred electrically conductive
fairing tail pieces 32, as electrically connected together by
conductors 33, form the second electrode 18. Cathode electrode 18
is insulated from electrode 17, and the return path from electrode
17 to electrode 18 is through the intervening sea water 11. It will
be apparent that there are not two towed cables behind towed body
10 to be separately handled and maintained in a tangle-proof
state.
[0022] Electrical conductors 33 extending between fairings 30 also
serve additional mechanical functions in that they are strung
tightly enough to prevent adjacent fairings from excessive rotation
in respect to each other, but are also strung loosely enough to
allow spacing between adjacent tail pieces to increase as required
when the tow cable is wound over a drum in known fashion.
[0023] DC electrical power as noted is provided across electrodes
17 and 18 for the open loop magnetic method of minesweeping. Since
AC power of low current and high voltage is provided to towed body
10 along tow cable 14, the high voltage, low current AC is
transformed to low voltage, high current AC at the towed body 10 by
transformer 19, and is then rectified by rectifier 20 to provide
the constant level or pulsed DC power required. The power
conversion electrical elements are shown schematically at cut-out
21 in FIG. 2, and as transformer 19 and rectifier 20 in FIG. 5.
[0024] Additionally illustrated schematically in FIG. 2 at cut-out
22 is an acoustic device that may take various well-known forms.
One or more such transducers may be located in towed body 10.
Accordingly, towed body 10 provides complementary magnetic and
acoustic influence signatures for minesweeping. The acoustic source
generally will produce a sweep path width that equals or exceeds
the magnetic sweep path width, in order to deal with dual influence
mines.
[0025] The sweep cable 16 and aft electrode 17 may be stowed on a
small winch 23 contained within an open and hollow rear end of
towed body 10, cable 16 and electrode 17 being deployed therefrom
to the FIG. 1 position during minesweeping and reeled back into
towed body 10 after use prior to retrieval of towed body 10. The
winch 23 may be controlled from control signals from the towing
platform.
[0026] Referring to FIG. 5, transformer 19 and rectifier stack 20
generate considerable heat in operation. Rather than utilizing
enclosed waterproof boxes and cooling plates aboard towed body 10,
the transformer 19 and rectifier 20 are each completely
encapsulated within very thin and conformal waterproof coatings 24,
25 respectively of material which may for example be a moldable
polymer. The sealed transformer 19 and rectifier 20 are in turn
mounted on towed body 10 so that the encapsulation layers 24, 25
are directly exposed to the sea water, thereby allowing heat
conduction directly through the thin layers 24, 25 to the sea
water. The transformer 19 and rectifier 20 may for example be
mounted in an internal cavity of body 10, which cavity is flooded
with sea water. Alternatively, they may be mounted in a pocket in
the side wall of towed body 10 exposed to the sea water.
Alternatively a tunnel may pass through a portion of towed body 10
through which sea water passes, the transformer 19 and rectifier 20
then being mounted within or on the side wall of said tunnel.
Waterproof pigtails 26 shown schematically in FIG. 5 in turn pass
between transformer 19 and rectifier 20 respectively and the power
connections internal to towed body 10. This cooling aspect of the
present invention provides for very efficient cooling and component
design to minimize size and weight on the towed body 10.
[0027] Solely as an exemplary embodiment of one form of the present
invention, the following parameters may apply in addition to the
parameters of electrode 18 mentioned above:
1 Length of towed body 10 10 feet Diameter of towed body 10 16
inches Length of sweep cable 16 250 feet Length of anode electrode
17 150 feet Diameter of cable 16 and .65 inches electrode 17
Diameter of cable 34 .40 inches Length of cathode electrode 150
feet AC power along towing cable 14 19 kilowatts DC current to
anode electrode 17 400-1000 amps DC power to anode electrode 17 16
kilowatts Weight (in air) of towed body 1000 pounds Tow speed of
system Up to 50 knots Field strength 4 MGauss Weight (in air) of
cable 16 230 pounds and electrode 17 Length of a fairing 30 3-6
inches in the direction of cable 14 Length of a fairing 30 4-6
inches perpendicular to cable 14
[0028] It will be seen from the above parameters that a very light
weight, small size open loop magnetic field system is provided,
including simplified electrode handling and efficient cooling.
[0029] It will be appreciated by persons skilled in the act that
numerous variations and/or modifications may be made to the
invention without departing from the spirit and scope of the
invention. The present embodiments are, therefore, to be considered
as illustrative and not restrictive.
* * * * *